大鼠胚胎神经上皮细胞侧脑室移植后存活及分化的实验研究

目的：观察大鼠胚胎神经上皮细胞同种脑移植后的存活及生长分化状况。方法：孕12d大鼠剖腹取胚胎，剥离神经管，胰酶消化后获取神经管壁上的神经上皮细胞，然后植入其父体侧脑室中，分别于移植后10d,14d,21d,28d灌注取脑，肜HF染色及神经元特异烯醇化酶（NSE），胶质纤维酸性蛋白（GFAP）免疫组织化学方法检测胚胎神经上皮细胞移植后的存活及分化状况。结果：神经上皮细胞侧脑室移植后多贴附于脑室壁形成细胞团块，有的随脑脊液循环至第三脑室生长，随时间延长移植物增大，HE染色见脑室内有成团的移植细胞，免疫组织化学染色显示移植细胞团内既有NSE－免疫阳性细胞，也有GFAP－免疫阳性细胞，移植物周围多为GFAP－免疫阳性细胞。结论：胚胎神经上皮细胞侧脑室移植后能够贴附脑室壁存活，并能分化为神经元和神经胶质细胞。     

苯巴比妥对癫痫大鼠空间学习和海马一氧化氮合酶表达的影响

为研究苯巴比妥（PB）对癫痫大鼠认知功能的影响和一氧化氮（NO）信号通路的参与作用。以海人藻酸（KA）致痫模型为研究对象，采用水迷宫测验、选择性神经型一氧化氮合酶（nNOS)抑制剂－7－硝基吲唑（7－NI）、RT－PCR技术观察PB对癫痫大鼠空间学习和海马nNOS mRNA表达的影响。结果显示，PB（60mg/kg ip.)有确切的抗癫痫作用。PB对未致痫大鼠空间认知功能无明显影响，但可加重癫痫大鼠空间认知功能的损害。PB和KA均有增加大鼠海马nNOS mRNA表达作用，两者有协同作用。小剂量7－NI（10mg/kg ip.)，可逆转PB（60mg/kg ip.)增加大鼠马nNOS mRNA表达的作用和对认知功能的影响。实验结果表明，NO信号通路参与了PB对KA模型认知功能的影响。     

神经降压素在大鼠应激性胃溃疡中的作用

选健康雄性Ｗｉｓｔａｒ大鼠１２２只，用脑室微量注射和放射免疫等分析方法，观察了中枢内、外源性神经降压素（ＮＴ）在大鼠束缚加水浸诱导的应激性胃溃疡中的作用。结果表明：（１）在大鼠应激性胃溃疡产生的同时，其血浆内神经降压素样免疫活性物（ＮＴＬＩ）的含量明显减少（Ｐ〈０．０５），而下丘脑、中脑、脑桥、延脑和垂体中ＮＴ－ＩＲ含量则明显升高（Ｐ〈０．０１）；（２）侧脑室注射抗ＮＴ血清中，大鼠应激性胃溃疡的产     

大鼠习瓣膜含神经肽Y血管性肠肽P物质和降钙素基因相关肽神经的分布及年龄变化

用免疫组织化学ＡＢＣ法结合葡萄糖氧化酶－ＤＡＢ－硫酸镍铵增强技术，研究了１月、８月和１８月龄大鼠心瓣膜中ＮＰＹ、ＶＩＰ、ＣＧＲＰ和ＳＰ免疫反应阳性神经纤维的分布。结果显示，以上４种含肽神经纤维在８月龄大鼠房室瓣上均有分布，密度顺序为ＮＰＹ＞ＣＧＲＰ＞ＶＩＰ和ＳＰ，含ＶＩＰ和ＳＰ神经纤维的密度相近。三尖瓣中含ＮＰＹ和ＳＰ神经纤维的密度大于二尖瓣，含ＶＩＰ和ＣＧＲＰ神经纤维的密度与二尖瓣的相近。瓣膜中的含肽神经纤维可从瓣膜附着处的心壁及乳头肌内的神经两个方向延伸而来。主动脉和肺动脉瓣内仅发现有ＮＰＹ神经。随大鼠年龄增长，房室瓣中含ＮＰＹ神经的密度有增加趋势。含ＣＧＲＰ、ＶＩＰ、ＳＰ神经在１月龄大鼠房室瓣上的密度为零，在８月和１８月储时的密度与１月龄时的差异非常显著，８月和１８月龄时的密度间无明显差异。１月龄和１８月龄大鼠的主动脉和肺动脉瓣上，未见到４种含肽神经。我们的结果为心瓣膜的神经支配提供了新的资料，但这些含肽神经在心瓣膜的作用尚待探讨。     

脊髓诱发电位在糖尿病神经病变早期诊断中的价值

在８０例Ⅱ型糖尿病患者，观察了正中神经和胫后神经刺激引起的脊髓诱发电位（ＳＣＥＰ）。结果表明，糖尿病患者ＳＣＥＰ的Ｎ＿（１３）、Ｎ＿（２０）潜伏期均比正常人明显延长（ｐ＜０．００１），并可发现无神经病变征象的亚临床型神经损害；同时，Ｎ＿（１３）、Ｎ＿（２０）潜伏期与病人的病程、病情及神经病变征象呈正相关（ｒ＝０，２５－０．５８，ｐ＜０．０５－０．０００１）．而与空腹血糖水平无关（ｒ＝０．０５－０．１１，ｐ＞０．０５）。提示ＳＣＥＰ检查有助于糖尿病神经病变的早期诊断和疗效观察。     

黑质区微量注射神经降压素对帕金森氏病大鼠模型的影响

制作帕金森氏病大鼠模型，观察其黑质区注射微量神经降压素的效应。结果表明：９１）黑质区注射６－羟基多巴胺２１天后，大鼠出现帕金森氏病的行动迟缓，强直和震颤等三大症状，以及股四头肌肌电图群放电位频率为４－８次／ｓ的动物模型；（２）黑质区注射不同剂量的神经降压素，经过一定时间后，大鼠模型的强直和震颤症状出现不同程度改善。     

异体神经移植后再生神经的荧光逆行标记

本文用ＷＩＳＴＡＲ大鼠作为实验模型，切除１ｃｍ坐骨神经，再用同系ＷＩＳＴＡＲ大鼠从骨神经行异体桥接，修复坐骨神经的缺损。用ＦＬＵＲＯ－ＧＯＬＤ（Ｆ．Ｇ）或ＦＡＳＴ ＢＬＵＥ（Ｆ．Ｂ）两种荧光标记物，进行示踪检验，证实ＷＩＳＴＡＲ鼠异体神经桥接能修复周围神经的缺损。     

糖尿病大鼠神经形态和山梨醇含量的变化及黄腐酸钠的作用

本研究观察糖尿病大鼠神经元梨醇、神经形态变化及探讨黄腐酸钠对其防治效果。成模6个月后观察（1）目前剂量的黄腐酸钠治疗6个月未能影响糖尿病动物的高血糖。（2）糖尿病组神经山梨醇明显增高；黄腐酸钠治疗组神经山梨醇明显低于糖尿病组，接近对照组水平。（3）糖尿病组有髓神经纤维密度明显低于对照组，电镜下可见神经纤维结构改变；黄腐酸钠治疗组有髓神经纤维密度明显高于糖尿病组，但尚低于对照组，神经纤维超微结构改变黄腐酸钠组较糖尿病组明显减轻。以上提示糖尿病大鼠在病程6个月时出现早期糖尿病神经病变，黄腐酸钠可一定程度地抑制实验性糖尿病周围神经病变的进展。     

胸腺的神经支配

胸腺的神经支配支晔，李淑芬（华北煤炭医学院，解剖学教研室，唐山０６３０００）神经免疫调节（Ｎｅｕｒｏ－ｉｍｍｕｎｏ－ｍｏｄｕｌａｔｉｏｎＮＩＭ）是近年来神经科学中出现的一个较新的概念。它协调神经系统、内分泌系统和免疫系统的相互作用，构成机体的整合系统...     

橙皮苷对STZ－糖尿病大鼠周围神经结构和功能的影响

本实验在链脲菌素（ｓｔｒｅｐｔｏｚｏｃｉｎ，ＳＴＺ）导致的糖尿病大鼠观察了橙皮苷（ＨＥ）对周围神经非酶糖基化作用、运动神经传导速度（ＭＮＣＶ）及其超微结构的影响，并与氨基胍（ＡＧ）进行比较。结果表明，ＨＥ与ＡＧ一样，均可明显降低神经组织中自发荧光的非酶糖基化终产物（ＡＧＥ＿ｓ）含量，并可改善ＭＮＣＶ，减轻神经脱髓鞘等病理改变。提示橙皮苷对ＳＴＺ－糖尿病大鼠神经病变有预防作用。     

Congenital giant axonal neuropathy

Giant axonal neuropathy (GAN) is a distal sensorimotor neuropathy, characterized by neurofilamentous axonal swellings, with usual onset at 2 to 3 years of age. We report a case of congenital GAN with hypotonia at birth. At 7 months of age, nerve conduction studies showed almost complete lack of sensory and motor responses in the lower extremities. A sural nerve biopsy specimen disclosed absence of myelinated axons. Autopsy, following death at 15 months of age, revealed axonal swellings in peripheral nerves and distal degeneration of long spinal cord tracts. The neurofilamentous content of the axonal swellings was confirmed by Glees-Marsland staining and immunoperoxidase reaction with antibodies to neurofilaments. Axonal swellings did not stain with periodic acid-Schiff and were not seen in the cerebral cortex or brain stem, distinguishing this process from infantile neuroaxonal dystrophy. This patient illustrates congenital GAN with subsequent rapid progression.     

Acetylcholinesterase in the rat neurohypophysis is decreased after dehydration and released by stimulation of the pituitary stalk

Specific acetylcholinesterase and non-specific cholinesterases are present in all three lobes of the rat pituitary gland. This paper describes two new observations on hypophyseal acetylcholinesterase. Firstly, a prolonged increase of neurohormone secretion evoked by dehydration and sodium loading was accompanied by a decrease in the acetylcholinesterase activity localized to the neural lobe, where acetylcholinesterase has previously been demonstrated in fine nerve fibres. Secondly, electrical stimulation of the pituitary stalk in vitro elicited the release of acetylcholinesterase and non-specific cholinesterases from the combined neural and intermediate lobe indicating that the enzyme can be released from nerve endings in the hypophysis by action potentials. The observed loss of enzyme activity during dehydration may be the consequence of a prolonged activation of cholinergic nerves in the gland, leading to an increased release of acetylcholinesterase, which is not immediately replaced by fresh enzyme. The decrease in acetylcholinesterase in the neural lobe during dehydration may also be connected with its peptidase function and thus with the previously observed loss of substance P from the neural lobe during dehydration [Holzbauer et al. (1984) Neurosci. Lett. 47, 23-28].     

Effect of water and salt intake on pituitary catecholamines in the rat and domestic pig

The dopamine content of the combined neural and intermediate lobes of the rat pituitary gland was increased when the secretion of posterior lobe hormones was maximally stimulated by a restricted water intake followed by the administration of NaCl in the drinking water (dehydration). This was accompanied by vasodilatation in the posterior lobe and by an increase in the intensity of catecholamine fluorescence in the perivascular nerve fibres. The quantity of noradrenaline in the neural and intermediate lobes, which amounts to about 10% of that of dopamine, was also increased after dehydration. Bilateral removal of the sympathetic superior cervical ganglia did not prevent the rise in pituitary dopamine levels after dehydration but the perivascular catecholamine-containing nerve fibres were no longer detectable. The operation caused a decrease in the noradrenaline content of the neural and intermediate lobes by about 50% in rats on normal water intake and in dehydrated rats. Thus, one half of the noradrenaline present in the neural and intermediate lobes is not contained in vasomotor fibres or other nerve fibres with cell bodies in the superior cervical ganglion. The increase in pituitary dopamine levels after dehydration was also observed in domestic pigs.It is concluded that the increase in the concentration of dopamine in the combined neural and intermediate lobes that follows dehydration and salt-loading does not occur in the perivascular sympathetic nerve fibres and that it may be related to the fall in the pituitary content of oxytocin and vasopressin.     

Calcitonin gene-related peptide (CGRP)-immunoreactive nerve terminals in the whole mount preparations of the dog urethra.

To visualize the entire shape of the intraepithelial nerve fibers, whole mount preparations of the dog urethra were produced and immunostained with an antiserum against CGRP, one of the predominant substances contained in the nerves. The immunoreactive nerves in the lamina propria were smooth (non-beaded) in appearance and weak in immunoreaction. Within the epithelium, they displayed typical beaded profiles and were intense in immunoreaction. The intraepithelial fibers branched and wound into an extensive network with wide meshes ("reticular terminal"). The bead-like swellings included large ones resembling Herring bodies in hypophyseal neurosecretory fibers. Another type of nerve terminal, consisting of fine and weakly immunopositive fibers, was also found in the epithelium. These branched in dendritic or in dense bouquet-like fashion, occupying smaller areas ("bouquet-like terminals). Vesicular swellings often characterized these terminals, though they were smaller and more uniform in size and far less in their amount of immunoreactive substance than were the swellings in the reticular terminals. Both types of nerve terminals originated from the same nerve trunk. The connection between the reticular and bouquet-like terminals, which may presumably represent secretory and receptive parts, respectively, morphologically supports the possible occurrence of an axon reflex in the urethral CGRP neurons. Our whole mount preparations, when doubly stained with CGRP and serotonin antibodies, further revealed the CGRP-positive reticular terminals being closely associated with serotonin- or CGRP-immunoreactive paraneurons dispersed in the epithelium.     

大鼠视上核神经分泌细胞的衰老形态变化

本文选用青年(3个月)、成年(10—12个月)和老年(28—30个月)雄性Wistar大鼠,对其下丘脑视上核神经分泌细胞分别作了光镜和电镜观察与测定。结果表明:老年大鼠视上核前部的神经分泌细胞密度与细胞核体积明显低于青年和成年大鼠,提示老年大鼠视上核有神经元消失和细胞活性降低的表现;神经分泌细胞核周质内的醛复红阳性颗粒未测出三个年龄组大鼠间的差异,含醛复红阳性颗粒的胞突在老年时却显示增粗和膨大;老年动物神经分泌细胞超微结构的主要变化为神经分泌颗粒和脂褐素增加,尤以后者为甚。老年大鼠少数神经分泌细胞还表现有粗面内质网和核蛋白体减少,排列紊乱,池囊扩张和脱颗粒,高尔基复合体池囊变窄或扩张,胞质和胞突内有自噬体样物质出现等衰老改变;多数细胞胞质内的其他结构同青年和成年大鼠者相似。此外。老年大鼠视上核神经毡结构中有多层膜包绕胞突,终末和突触等的鞘样结构出现增多。本研究表明大鼠衰老时视上核神经分泌细胞活性降低。     

血管加压素免疫反应神经纤维也存在于中国树鼩垂体门微静脉管壁内

采用ABC免疫组化和DAB／H2O2／Ni加强技术以及兔抗血管加压素血清，观察了血管加压素免疫反应神经纤维在中国树垂体门脉系统的门微静脉壁内的存在。证明此纤维呈细丝状，在门微静脉壁内呈环行密集分布，可能呈螺旋形走向，纤维间界限不清，有的地方可见血管内皮细胞内含有血管加压素免疫反应产物。空白对照试验和抗催产素血清对照试验的结果表明；门微静脉壁内的着色反应为特异性的血管加压系免疫反应。本文讨论了门微静脉壁内血管加压素免疫反应神经纤维的来源、去向和与垂体前叶内其它肽能神经纤维的关系。     

Nerve growth factor receptor in neural lobe of rat pituitary gland: immunohistochemical localization, biochemical characterization and regulation

Summary Nerve growth factor-receptor immunoreactivity was detected in the neural lobe of the pituitary gland in developing and adult rats of both sexes. The presence of nerve growth factor receptor in the neural lobe was further verified by a quantitative¹²⁵I-nerve growth factor/crosslink/immunoprecipitation assay and subsequent visualization by SDS-PAGE autoradiography. Nerve growth factor-receptor immunoreactivity was detected in the neural lobe of postnatal 5-day-old rats, had increased by 2 months and was much higher in 1-year-old rats. In 2-month-old rats, no immunoreactivity was observed in anterior or intermediate lobes. Pituitary stalk transection in young adult rats greatly increased the expression of nerve growth factor-receptor immunoreactivity in the neural lobe, although the staining pattern remained the same. This increase began 3 days after surgery, and reached peak levels at approximately 15 days. Other physiological or non-physiological changes did not alter the nerve growth factor-receptor immunoreactivity in the neural lobe; these changes included dehydration, pregnancy and lactation, castration of male rats, bilateral superior cervical ganglionectomy and intraventricular injection of colchicine. Intravenously injected¹²⁵I-nerve growth factor was specifically accumulated in both normal and denervated neural lobe. Nerve growth factor-receptor immunohistochemical electron microscopy showed that the receptor-positive cells are fusiform and found both inside and outside the basal lamina that delimits the neural lobe parenchyma. Based upon the anatomical localization, morphology and response to axotomy, we identify, at least the perivascular component, as microglia. These data suggest a role for nerve growth factor and/or nerve growth factor receptor in microglial function.     

Blood-nerve and blood-brain barrier permeabilities and nerve vascular space in Fischer-344 rats of different ages

The permeability-surface area product (PA) of [3H]- or [14C]sucrose at the blood-nerve barrier (BNB) of the sciatic nerve; and at the blood-brain barrier (BBB), were determined in Fischer-344 rats at 3, 11 and 31 months of age. PA was determined by using an in vivo i.v. bolus injection of radiotracer with two-time point graphic and quantitative autoradiographic methods. Vascular space and water content of the tibial nerve of these rats also were determined using quantitative morphometry and dry and wet weight ratios, respectively. There was no significant difference between mean PA(BNB) in any age group [(PA(BNB) at 3 months = 1.2 +/- 0.1 (mean +/- S.E.), at 11 months = 1.8 +/- 0.3; and at 31 months = 1.4 +/- 0.2 x 10(5) ml/s . g wet wt; n = 5-8 rats], nor any difference in PA(BBB). The mean ratio (%) of surface area of endoneurial blood vessels/nerve cross-section of the tibial nerve also did not differ between any group [3 months: 16 +/- 2 vessels; mean surface area ratios = 2.20 +/- 0.10%, n = 5; 11 months: 22 +/- 3 vessels and 2.48 +/- 0.21%, n = 5; 11 months: 22 +/- 3 vessels and 2.48 +/- 0.21%, n = 5; and at 31 months: 26 +/- 1 vessels and 2.40 +/- 0.23%, n = 4). The mean nerve water in rats at 31 months was 64.8 +/- 1.1% wet wt and did not differ from that at 11 months (66.0 +/- 0.6% wet wt) or at 3 months (65.1 +/- 1.0% wet wt) (n = 5-8 nerves). Our results indicate that BBB and BNB integrities are not altered in senescent Fischer-344 rats.     

Ultrastructural and immunocytochemical studies of the viscacha (Lagostomus maximus maximus) pituitary pars tuberalis

The hypophyseal pars tuberalis (PT) has been the focus of numerous studies attempting to understand its physiological role in the reproductive regulation and modulation by the neuroendocrine system. Ultrastructural studies of the PT in a number of species have shown that it consists of a well-developed hypophyseal area with important secretory activity, demonstrated by the abundance of secretory granules in the cytoplasm and the marked blood irrigation. This article describes ultrastructural and immunocytochemical aspects of the PT in viscachas captured in their habitat. The cell types identified were PT-specific cells, agranulated cells, and Folliculostellate cells. PT-specific cells are divided into type I and II. Type I cells have cytoplasms with secretory granules of 150-500 nm diameter. The secretory granules of type II PT-specific cells are 65-200 nm in diameter. Both cellular types exhibit numerous nerve endings on the plasmatic membranes. Agranulated cells exhibit nuclei with lax chromatin, mitochondria, phagosomes, scarce Golgi complex, and rough endoplasmic reticulum. Folliculostellate cells exhibit an irregularly shaped and moderately condensed nucleus. All the described cellular types exhibit deposits of cytoplasmic glycogen. The immunocytochemical study revealed the presence of cells immunostained for LH-beta and FSH-beta in the PT caudal zone. ACTH was only detected in the zona tuberalis. No staining was observed with antiprolactin, anti-TSH-beta, and anti-GH sera. Folliculostellate cells exhibited staining with anti-S-100. The results demonstrate that the viscacha PT is a hypophyseal zone with specific cellular types, which exhibits evident secretory activity. The presence of nerve endings suggests neural control of the function of PT cells.     

Age-dependent changes in noradrenergic innervations of the frontal cortex in F344 rats

Noradrenergic innervations of the frontal cortex with advancing age (9, 13 and 25 months) in male F344 rats were quantified by immunohistochemistry for dopamine-beta-hydroxylase (DBH), which is a marker enzyme for noradrenergic axons. The density of DBH-positive axons, varicosities (swellings along an axon from which noradrenaline is released), and the number of varicosities per unit length of axon were measured in the frontal cortex. We found that the density of axons and varicosities significantly decreased at an earlier stage of aging (9-13 months), but not at a later stage (13-25 months). On the other hand, the number of varicosities per unit length of axon did not change with age. The result shows that the density of varicosities, which represent the synapses of noradrenergic neurons, decrease in the frontal cortex in the early aging process.